Manufacture of seamless tubes.



. V s.. WESCHE-R. [M NUFACTURE OF SEAMLESS TUBES.

APP1;ICATI0N FILED APR. 21. 1917- Patented Oct. 8, 1918.

3 SHEETSSHEET F'IE.E.

' F'IG.E.

S. E. DIESCHER.

MANUFACTURE OF SEAMLESS TUBES.

APPLICATION FILED APR. 21. 1912.

1. ,280,683 v Patented Oct. 8, 1918.

3 SHEETS-SHEET 3.

115.4- was.

swis th SAMUEL E. DIESCHER, 0F PITTSBURGH, PENNSYLVANIA.

MANUFACTURE OF SEAMLESS TUBES.

Specification of Letters Yatent.

Application filed April 21, 1917. Serial No. 163,644.

To all whom it may concern:

Be it known that I, SAMUEL residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvement in the Manufacture of Seamless Tubes, of which improvement the following is a specification.

' 1n the manufacture of seamless tubes, the methods employed in reducing the wall thicknesses to the required gage may be classed under two heads; 2'. 6., those in which reduction is efiected along lines substantially parallel with the axis of the tube and those in which reducing pressure is applied at an angle to the axis of the tube.

The first method is generally carried out by passing the tubular blank through grooved rolls. As reduction in such rolls is not uniform, being greatest in direction substantially at right angles to the axes of the rolls, it is necessary to pass the tube a number of times between the rolls, it being turned on its axis intermediate such passes. Although this method involves considerable time and labor due to the necessarily repeated passes, it is preferable to the method in which reduction is substantially uniform at all parts around and along the tube brought about by applying reducing pressure at an angle to the axis of the tube.

1 The serious drawback incident to this latter method is the distortion from a circular shape due to the peripheral flow of metal.

Many attempts have been. made to overcome this distorting action, as for example, guide bars have been placed intermediate the angularly arranged reducing surfaces in order to prevent the metal of the tube from swelling out intermediate the points ofre duction. \Vhile such guide bars will, to some extent, prevent the distortion, the rubbing of the highly heated metal along the guides, causes such a rapid wearing down of the guides that in rolling one tube there will be a detrimental distortion ofthe guiding 4 surface; this distortion, due to wear, is not uniform and cannot be taken up by adjustment. In addition to this undesirable result, the expense involved in frequent renew als of the guide bars making the changes,

and the loss of time in has rendered the em- E. DIESGHER,

- rolls, the

ployment of guides commercially impracticable.

The object of the invention described herein is to provide guiding or retaining surfaces which will move in the direction of the axis of the tube thus reducing and making uniform the frictional wear and which will be so arranged as to prevent cross-sew tional distortion of the tube and which are adjustable for taking up the wear. QThe.

invention is hereinafter more fully. described and claimed.

Patented Oct. s, 1918.

In the accompanying drawing forming a I part of this specification, Figure 1' is an elevationof the angularly arranged rolls of the tube mill and embodying grooved rolls arranged to prevent distortion of a tubeintermediate the reducing rolls; Fig. 2 is an elevation at right angles to Fig. 1 and having portions broken away. Fig. 3 is a top plan view showing a form of mill in which discs are employed in lieu of rolls for effecting reductiomand Figs. 4: and 5 are sectional views on planes indicated by the lines IVIV and VV, Fig. 3. v

In the practice of the invention, the reducing rolls 1 are so supported in suitable housings that their axes will be oppositely but equally inclined to the line of move ment of the tube being operatedon. The operative surfaces of the rolls 1 consist of reducing portion a and finishing portion b. The reducing portion may be made tocorrespond in contour, in the working plane, (said plane being at right angles to the plane of section in Fig. 2 and lying in the axis of the tube) to a section of sphere, while the finishing portion b is made substantially parallel with the axis of the billetin the working plane. ,The rolls are preferably so mounted that planes coincident with the axes of the rolls will intersect in a line at right angles to the axis of the tube being reduced.

As shown in Figs. 8, 4:, and 5, disks 4; may be substituted for the rolls 1, the opposing faces of these disks being shaped to form reducing and finishing surfaces 0 and d, corresponding to the surfaces a and b of the rolls 1. Asis the practice when employing disks in lieu of angularly arranged axes of rotation of the disks are out of line. A

It will be understood that the term roll is hereinafter used as covering not only the cylindrical form as shown in Figs. 1 and 9, but also other forms capable'of effecting the reductions and metal movements herein describechsuch for example, the disk forms shown in Figs. 3, 4, and 5.

These rolls being set to move at an angle to the article will cause a forward flow of metal and also to a greater or less extent a peripheral flow, resulting in a bulging out of the metal, and in order to prevent this bulging out between the rolls due to the peripheral flow, guide rollers 2 are so mounted above and below the reducing rolls as to bear upon the article intermediate the points of contact of the reducing rolls therewith. These guide rollers are preferably made of a width approximately equal to theshortestdistance between the reducing rolls and are peripherally grooved so as to bear upon the article between the points of contact of the reducing rolls with the articles, As it is desirable that these guide rollers should bear upon so much of the article-as is being acted upon by thereducingportions a of the rolls, they are formed with a radius substantially equalto the radius .of the reducing portions of the rolls 1, and preferablyare so mounted in the housing that a plane containing the axes of the guide rollers will contain the line connecting the nearest points of the reducing surfaces of the rolls, said plane bein perpendicular to the axis of thearticle being rolled.

As it is preferred that the guide or preventive rollers should be positively driven, pro ision is made for connecting the rollers to a suitable driving mechanism by means of spindles 3. The preventive rollers are-so adj ustedthat the pass formed between their operative surfaces will have an opening sub stantially equal to the external diameter required in the finished tube. These operative surfaces will have a more or less effective grip on the metal by reason of the latter being forced out against the surfaces of the preventive rollers by the action of the reducing rolls, and to the extent or effectiveness of such grip, the preventive rollers can be. employed for controlling the action or effect of the reducing rolls. As for example, if it should be found that the metal of the tube movesforward too freely from the reducing rolls, and binds on the mandrel, the preventive rollers can be given a slower peripheral speed and thereby retard the forward movement of the metal. If, on the o her hand, it is found that the desired relation of the longitudinal and peripheral llnW of the metal is not maintained. and hence there is too great a tendency of dis l'ortion, the bulging metal cruising the proventiv'e rolls to more effectively grip the a" metal, then the preventive rollers can be speeded up and exert a longitudinal pull on the article. This pull in the direction of movement of the article will increase the longitudinal flow of the metal and consequently reduce the tendency of the metal to bul e out intermediate the reducing rolls.

1%16 following are characteristics of the method and combination described herein 1. The working faces of the reducing rolls are so shaped as hereinbefore describechas to impart to the billet as it moves peripherally to the guide rolls, a contour conforming1 with the curved surfaces of the guide r0 5.

2. The guide rolls having positive rotation Will permit the passage of the metal where the reduction is occurring to move through the guiding surfaces without friction, or with friction greatly reduced. This reduction of friction Will be in proportion to the speed at which the guiding surfaces are driven.

3. Theguiding surfaces moving at a greater speed than the longitudinal speed of the material passing'out of the reducing rolls, will effect a stretching out or longitudinal displacement of the surplus material which would otherwisemove circumferentially. 1

Each of the above characteristics is a distinct advance in'the art of producing seamless tubes by inclined rolling surfaces. The wear of the guide rolls will occur in such a manner as not to disturb the contour of the guide rolls, as When not driven positively, they would be rotated by longitudinal travel Of the billet and finished tube through the mill, and by reason of such rotationthe wear must necessarily be uniform all around the entire'circumference of the guide rolls. If stationary guides were used, this wear would never be uniform since the pressures would be applied to the guides by the circumferential displacement of the metaLin the Work piece in such a manner that great wear would occur at one point and very little at another in the length of the guides.

I claim herein as my invention:

' 1. The method herein described, which consists in subjecting a blank to the reducing action of a plurality of surfaces arranged at different points around the blank and at an angle to the axis of the blank whereby the metal is caused to flow longi tudinallv and peripherally, and simultaneously controlling the eripheral flow by surfaces acting on the lank peripherally intermediate the points of contact of the re ducing surfaces and moving in the direction of the longitudinal flow of metal.

2 The method herein described, which consists in subjecting a blank to the reducing action. of surfaces arranged at an angle to the axis of the blank, whereby the metal caused to flow longitmlinally and pcripherally, and simultaneously applying transverse pressure to the blank at points peripherally intermediate the points of reduction by surfaces moving in the direction of the longitudinal flow of metal whereby distortion due to peripheral flow is prevented. g

3. The method herein described, which consists in subjecting a blank to the reducing action of surface arranged at an angle to the axisof the blank, whereby the metal is caused tofiow longitudinally and peripherally, and simultaneously applying pressure to the blank at points peripherally intermediate the points of reduction, such ressure operating longitudinally of the blank and controlling the peripheral flow of the metal.

which consists in working the blank between surfaces acting at an angle to the blank and so formed as to leave a profile on the blank that will conform with the surfaces of moving guides located circumferentially intermediate, the reducing surfaces and sepa- .rately mounted in a plane substantially co inciding with the center line of the billet.

"5.In a rolling mill, the combination of rolling members arranged tooperate at an angle to the direction of feed between the rolls, and rolls arranged intermediate thefirst or reducing rolls, and having their axes at right angles to the direction of feed ofthe article being rolled and in a plane intersecting the axis of the blank at a point where said axis intersects aline between the nearest pointsof the reducing rolls. V

6. In a rolling mill the combination of guide rollers having grooved peripheries and reducing members so arranged that their reducing surfaces will move at an angle to the axis of the article being rolled,

aid guide rollers being arranged intermediate the reducing members and having their axes at right angles to the direction'of feed of the article being rolled, the reducing members having curved surfaces of substantially the same radius as that of the guide rollers at the base of the grooves.

7 In a rolling mill the combination of v guide rollers having grooved peripheries,

. i and reducing members so arranged that 4. The method of reducing hollow blanks their reducing surfaces will move at an acute angle to the axis of the article being rolled,

said guide rollers being arranged intermediate the reducing members and rotatable independently thereof and having their axes at right angles to the direction of feed of the article being rolled and in a plane intersecting the axis of the article at a point where said axis intersects a line between the nearest points of the reducing rolls.

In testimony whereof,I have hereunto set my hand.

L SAMUEL E. DIE SCHER. Witness: 2 I MARGARET M. Reunion, 

